Load Cell Connection

Load Cell Connection

Table of Contents

Step 1 – Let’s first connect the Load Cell to the Strain Gauge Amp

Step 2 – Let’s connect the Strain Gauge Amp to the Motor

Step 3 – Finally let’s connect the Load Cell to the Knee


Step 1: Let’s first connect the Load Cell to the Strain Gauge Amp

Materials:

14 Position Rectangular Housing Connector (vendor: Digi-key Instruments, part no: WM1722-ND)

1 x 14 Position Rectangular Housing Connector (vendor: Digi-key, part no: WM17001-ND)

1426-28 AWG Crimp (vendor: Sunrise Instruments, part no: WM2023-ND)

1 x Loadcell (vendor: Sunrise Instruments, part no: 3564F)

1 x Strain Gauge Amplifier (vendor: Dephy, part no: 6ch)

1 x Surface Mount (vendor: Digi-key, part no: WM7608CT-ND)

Tools:

1 x Crimping Tool by Molex (vendor: Digi-key, part no: WM15815-ND)

1 x Wire cutter

Instructions:

1)  Cut 11 cm of black loadcell cable using a wirecutter

2) Strip 4 cm off of the insulation of the black load cell cable

3) Take wire off

4) Match input and output channels of the loadcell to those of the strain gauge amp.

Refer to the schematics below:

5) Put 26-28 AWG crimp to all ends of the loadcell cable using the crimping tool.

Refer to the crimping video below if you have not used the crimping tool before:

6) Insert the crimped wire into the housing connectors:

For the 4pins connector in the strain gauge amplifier, we used 4 Position Rectangular Housing Connector and 26-28 AWG Crimp.
 
For the 14pins connector in the strain gauge amplifier, we used 14 Position Rectangular Housing Connector and 26-28 AWG Crimp.

7) Insert the housing connectors into their corresponding surface mounts in the strain gauge amp.


Step 2 – Let’s connect the Strain Gauge Amp to the Motor

Materials:

(*Materials in the pictures are listed from top to bottom and then left to right.)

1 x 10ft. 26AWG wire (vendor: McMaster, part no: 2674N21)

1 x Shrink wrap

120 Position Rectangular Housing Connector

1 x 6 Position Rectangular Housing Connector

626-28 AWG Crimp (vendor: Sunrise Instruments, part no: WM2023-ND)

Tools:

1 x Wire cutter

1 x Crimping tool

1 x Hot glue

1 x Heat gun


Instructions:

1) Cut 4 wires (26AWG) to 30cm each

2) Expose 1mm wire from both ends.

3) Put 26-28AWG crimp on one end of all the wires using the crimping tool (these will be used to connect to the strain gauge amp)

Refer to the crimping video below if you have not used the crimping tool before:

Video showing how to crimp

4) Put 28-32AWG crimp on the other end of all the wires using the crimping tool (these will be used to connect to the motor)

5) Place the wires with the 26-28AWG crimp to 4 Position Rectangular Housing Connector

Refer to the schematic below:

6) Now we will separate the wires into 2 groups and place shrink wrap to cover all exposed wire

Group 1: Put side with 28-32AWG crimp to 20 Position Rectangular Housing Connector (these will be used to connect to the motor)

Refer to the motor schematics below:

Group 2 (i2c, SCL): Put side with 28-32AWG crimp to 6 Position Rectangular Housing Connector

Refer to the motor schematics again:

This image has an empty alt attribute; its file name is Screen-Shot-2020-02-26-at-6.48.57-PM-4-1024x762.png

7) Use hot glue at the intersection of crimps with the housing